s.mu.Unlock()
}

func (s *Weighted) notifyWaiters() {
	for {
		next := s.waiters.Front()
		if next == nil {
			break // No more waiters blocked.
		}

		w := next.Value.(waiter)
		if s.size-s.cur < w.n {
			// Not enough tokens for the next waiter.  We could keep going (to try to
			// find a waiter with a smaller request), but under load that could cause

					s.next.parent = s
				}
				// Add t first in s's wait list.
				s.waitlink = t
				s.waittail = t.waittail
				if s.waittail == nil {
					s.waittail = t
				}
				s.waiters = t.waiters
				if s.waiters+1 != 0 {
					s.waiters++
				}
				t.parent = nil
				t.prev = nil
				t.next = nil
				t.waittail = nil
			} else {
				// Add s to end of t's wait list.
				if t.waittail == nil {

	// the unlocking goroutine to the waiter at the front of the queue.
	// New arriving goroutines don't try to acquire the mutex even if it appears
	// to be unlocked, and don't try to spin. Instead they queue themselves at
	// the tail of the wait queue.
	//
	// If a waiter receives ownership of the mutex and sees that either
	// (1) it is the last waiter in the queue, or (2) it waited for less than 1 ms,

	}
	// This goroutine has set counter to 0 when waiters > 0.
	// Now there can't be concurrent mutations of state:
	// - Adds must not happen concurrently with Wait,
	// - Wait does not increment waiters if it sees counter == 0.
	// Still do a cheap sanity check to detect WaitGroup misuse.
	if wg.state.Load() != state {
		panic("sync: WaitGroup misuse: Add called concurrently with Wait")
	}
	// Reset waiters count to 0.
	wg.state.Store(0)

    }

    /** Performs a GAS operation on the {@link #waiters} field. */
    @Override
    Waiter gasWaiters(AbstractFuture<?> future, Waiter update) {
      while (true) {
        Waiter waiter = future.waiters;
        if (update == waiter) {
          return waiter;
        }
        if (casWaiters(future, waiter, update)) {
          return waiter;
        }
      }
    }

    /** Non-volatile write of the thread to the {@link Waiter#thread} field. */
    abstract void putThread(Waiter waiter, Thread newValue);

    /** Non-volatile write of the waiter to the {@link Waiter#next} field. */
    abstract void putNext(Waiter waiter, @CheckForNull Waiter newValue);

    /** Performs a CAS operation on the {@link #waiters} field. */
    abstract boolean casWaiters(

	if !evaluator.Handles(a) {
		return nil
	}
	waiter := newAdmissionWaiter(a)

	e.addWork(waiter)

	// wait for completion or timeout
	select {
	case <-waiter.finished:
	case <-time.After(10 * time.Second):
		return apierrors.NewInternalError(fmt.Errorf("resource quota evaluation timed out"))
	}

	return waiter.result
}

func (e *quotaEvaluator) addWork(a *admissionWaiter) {

	closed   uint32
	timer    *timer // timer feeding this chan
	elemtype *_type // element type
	sendx    uint   // send index
	recvx    uint   // receive index
	recvq    waitq  // list of recv waiters
	sendq    waitq  // list of send waiters

	// lock protects all fields in hchan, as well as several
	// fields in sudogs blocked on this channel.
	//
	// Do not change another G's status while holding this lock

			// needed, based on the number of available
			// unlocked OS threads at the time waiter
			// calls runtime.LockOSThread(), but the goal
			// of doing this every time through the loop
			// is to race thread creation with v.fn(want)
			// being executed. Via the once boolean we
			// also encourage one in 5 waiters to return
			// locked after participating in only one
			// question response sequence. This allows the

	// because c was closed.
	success bool

	// waiters is a count of semaRoot waiting list other than head of list,
	// clamped to a uint16 to fit in unused space.
	// Only meaningful at the head of the list.
	// (If we wanted to be overly clever, we could store a high 16 bits
	// in the second entry in the list.)
	waiters uint16

	parent   *sudog // semaRoot binary tree